1. Field of the Invention
The present invention relates to an apparatus and process for conducting a pretreatment of a sample prior to an analysis for the presence of specific sugar molecular chains.
2. Description of Related Art
The analysis of molecular sugar chains in samples of products is frequently conducted in laboratories. There are numerous examples of sugar molecular chains that are analyzed, such as D-glucose, L-fructose, etc. In conducting such an analysis, a pretreatment procedure is utilized to isolate the sugar molecular chains for labeling with fluorescence. This frequently occurs by taking the sample in a sample vial, and with the screw cap of the mouth portion of the sample vial removed. The sample vial is placed in a centrifugal stirrer with a reagent, for example, pyridylamination, which is mixed into the sample vial and stirred. The sample vial is then transferred to a heater and heated. Subsequently, the heated sample vial is transferred to an evaporator, where the excess reagents for pyridylamination are removed. The sample vial, with the reagents being evaporated away, is then returned to the centrifugal stirrer. A reducing reagent is then poured into the sample vial. If the pouring tip is with the sample vial, the tip is replaced prior to adding each reagent to prevent any contamination with the reagent. The reducing agent is then stirred, and the sample vial is again transferred to a heater for heating the sample. The heated sample vial is then returned to the centrifugal stirrer. The pouring tip is again replaced so that a first azeotropic reagent can be poured into the sample vial and stirred to ensure a thorough mixing. The tip can then be replaced again to pour a second azeotropic reagent into the sample vial, again followed by stirring. The sample vial is then transferred to an evaporator to again evaporate the reagents, with the sample vial then again returned to the centrifugal stirrer. Third and fourth reagents can again be poured into the sample vial in the same manner as previously described. The pouring tip is again replaced to accommodate a fifth azeotropic reagent for mixing in the sample vial. Again, the mixture is stirred and then transferred to the evaporator to conduct a further evaporation. The screw cap can be put onto the sample vial to close the mouth portion of the sample vial. The sample vial is then returned to its storing position.
As can be readily determined from the above procedure, a number of the process steps require repetitive removing and mounting of the screw cap onto the sample vial and a repetitive replacement of the reagent-dividing pouring tips with repetitive pouring of reagents in the sample vial and transfers of the sample vial between the centrifugal stirrer, the heater, and the evaporator. These steps are frequently labor intensive and have been manually conducted as part of the pretreatment before analysis for the presence of sugar molecular chains. The manual labor can not only be costly, but errors can occur and the reproduceability of the test procedure can accordingly suffer. Thus, the prior art is still seeking improved procedures and apparatus to provide an efficient pretreatment of samples for determining the contents of sugar molecules and the like.